/*
 *  Copyright (C) 2010 Matthias Buch-Kromann <mbk.isv@cbs.dk>
 * 
 *  This file is part of the MatrixParser package.
 *  
 *  The MatrixParser program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 * 
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Lesser General Public License for more details.
 * 
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.osdtsystem.matrixparser.features;

import java.util.List;
import java.util.Map.Entry;

/**
 *
 * @author Matthias Buch-Kromann <mbk.isv@cbs.dk>
 */
public class FeatureVectorFactory {
    public static final int UNION_METHOD_LIST = 0;
    public static final int UNION_METHOD_MAP = 1;
    public static final int UNION_METHOD_SET = 2;
    public static final int UNION_METHOD = UNION_METHOD_MAP;

    public static FeatureVector union(List<FeatureVector> featureVectors) {
        if (UNION_METHOD == UNION_METHOD_LIST) {
            return new UnionFeatureVector(featureVectors);
        } else {
            FeatureVector result = (UNION_METHOD == UNION_METHOD_SET)
                    ? new SparseBinaryFeatureVector()
                    : new SparseFeatureVector();
            for (int i = 0; i < featureVectors.size(); ++i) {
                for (Entry<Feature,Double> entry : featureVectors.get(i)) {
                    Feature feature = entry.getKey();
                    result.setValue(feature, result.getValue(feature) + entry.getValue());
                }
            }
            return(result);
        }
    }

    public static FeatureVector makeNodeFeatureVector() {
        //return new SparseFeatureVector(false);
        return new SparseBinaryFeatureVector();
        //return new SparseDuplicateDebugFeatureVector();
    }
}
